The objectives of the project remains the study of the physiologic role of cartilage lysozyme. Our recent findings indicate that a certain pool of cartilage lysozyme is selectively associated with hyaluronic acid forming a complex of such a nature that it cannot be broken by dissociative solvents such as 4M guanidinium hydrochloride in cesium chloride density gradients. It is, therefore, postulated that lysozyme can occupy certain proteoglycan-binding sites on the hyaluronic acid molecule therby regulating the size and/or degree of aggregation of the proteoglycan-aggregates. Furthermore, emphasis will be directed toward a detailed study of this hyaluronic acid-lysozyme complex by applying selective degradation of hyaluronic acid by Streptomyces derived hyaluronidase. This work will further extend into studies on low molecular weight proteins which act as trypsin or chymotrypsin or collagenase inhibitors. This aspect of the investigation will be pursued.